Minutes of the Sep 9, 2005 Tevatron Dept Meeting

1. Vladimir informed about coming reorganization in the AD (as well as in
other divisions) - more physicists will be asked to work on future
projects (ILC, PD, LHC, etc) while still be focused on Run II.

2. Ron on operations: 6 stores, lumi from 80 to 113e30, one ended
unintentionally due to flaky vacuum controls, after B11V separator spark 
reduced lumi to only 7 E30; after a store with lower proton lifetime (50
hrs), the proton vertical tune was raised and lifetime went up to 125 hrs;
there was a two shift access mid-week which was used to fix B0Q5 PSs+leak
check A49 separator + move tiltmeters and condition separators. Some 10-20
MeV energy mismatch was found to depend on front porch time - has to
be investigated (also, one has to look into MTF b0- drift measurement
data).

3. Sasha reported two successful attempts to change optics from beta*=35
cm to 28 cm in stores #4371 and 4374 - both times at lumi=60e30. The change
resulted in 3.5% CDF lumi gain and 7% in D0.  In the second attempt, tunes
and chromaticities landed almost where we wanted.  Alpha bumps moved CDF
vert waist position by some 5 cm to a better, but not optimal position - 
confirmed by the detector.

4. Vahid tested his application which stabilizes Tev orbits at LB (all
around the ring) - it reads all BPMs, makes SVD analysis (as in TOP) ,
computes the best way to correct using selected set of correctors, and
corrects - all that in 30 sec. After an obvious sign error was fixed, the
system stabilized 0.2-0.5 mm V & H orbit movements (excited by an extra
correctors) down to 0.04 mm.  Ron mentioned that the application should not
try to exceed 50A in any corrector it uses. Also, people mentioned that
special attention should be paid to the IP position; BPM readings
averaging might be beneficial, too.

5. Vahid also analysed TBT data (8k readings) in HEP store and by making
the FFT and SVD analysis showed that 12 Hz orbit vibrations are coming
from D0 and (less)A0 while B0 and C0 locations are sources of 17.5Hz
excitations. 40 Hz vertical orbit jitter comes from C0. Dean and Jerry
guess that the latter is because of iron plate floor vibrations induced
by fans.

6. Jean-Paul presented first results from a Digital Tune Monitor (DTM,
which he, Valery and Alexei Semenov pursue). This is a fast 16-bit ADC
which was supposed to see tune lines in residual beam motion detected at a
strip-line - and will work bunch-by-bunch.  So far hybrids were not
employed and the noise levels were about 20 microns rms (in a previous,
analog version, noise was 3 microns). More work to be done.

7. Dean reported 1st attempt to operate bent crystal collimator (BCC) at
980 GeV - very encouraging results: the collimator was found with the
4x0 beam and has been properly positioned. While changing the BCC angle
wrt to the beam some features of the channeling were found (like existance
of particles 4 mm off the main beam 10 m downstream the BCC) while some
other observations still need to be understood. Dean is ready for a EoS
study.

8. T:AGIDC[0:305] built by Randy shows every bucket intensity. It was
analysed by Vladimir : it shows the DC beam particles wander mostly in
one direction; bucket intensities in between the main bunches slowly grow
by factor of 3 over 24 hrs while intensity in satellites +2 and -2 stay
still.

9. Yuri explored how far up proton tunes can be moved while keeping pbar
tunes constant: at HEP the diff tune split is about 0.004 (H) and 0.007
(V); with Ron's mult (T55 "prot H+V tune", employs S4) one can get extra
0.007 (H) anf 0.005 V at S4=45A - that should be enough to move p-tunes
above 7/12 in HEP stores. Another 0.004-0.009 can be added if S3
circuit is employed and S7 used for coupling correction.

10. Vladimir made a quick look into effectiveness of recycling of pbars
(see doc-1954): protons are to be removed in the Tev at the EoS, pbars
decelerated to 150 GeV, extracted by sets of 4 to MI , decelerated there
with 53 and 2.5MHz RFs to 8GeV and sent to RR. Overall gain in the
integrated luminosity can be as big as (15-25)% for 30-20 hr long stores
(with currenly observed pbar longitudinal distributions in the Tev and
transfer efficiencies in Tev Mi and RR). Several issues discussed.


Minutes recorded by V. Shiltsev, edited by R. Moore